Automatic circuit-closer for electric heaters.



VI. H. FARLEY.

AUTOMATIC CIRCUIT CLOSER FOR ELECTRIC HEATERS.

APPLmATloN FILED MAR.`23,1916.

15.22%, l 95. Patented my 29, um.

.If I MTU/mns ilIIcH'AEI. HoUGH TABLET,

AnTHiml OF SEATTLE,

WASHINGTON, AssI'eNoiil or ONE-HALF To w. HAH, or SEATTLE, WASHINGTON.

'AUTOMATIC CIRCUIT-CLOSER FOR ELETRIC HEATERS.

Specification et Letters Patent.

Patented May 29, 1917.

Application led Iareh 23, 1916. Serial No. 86,135.

To all whom t may concern:

Be it known that I,

MICHAEL H. FARLEY,

a citizen of the United States, and a resident of Seattle, in the county-of of Washington, Improved Automatic King and State have invented a new and Circuit-Closer for Electric Heaters, of which the following is va full, clear, and

exact description.

vlThis invention relates to automatic circuit breakers or closers and has particular More definitely stated, one of pal objects of the invention automatic thermostatic switch or controller for use in connectionwith the princiis to provide an an electric sad iron, the saine being adapted not only to break the circuit when the iron attains a certain predetermined degree of heat and to again close ture of the iron such anature as adjusted' so as to vary the circuit when the temperabecomes reduced, but .is of to be easily and delicately that degree ofheat,

which makes the device adapted for higher or lower temperatures according to the desire of the operator-d With the foregoing and other objects in view, the invention consists ment and combination of in the arrangeparts hereinafter described and claimed, and while the invention is not restricted to the exact details of construction disclosed herein, still for the purposel of illustrating a ment thereof reference Vis panying drawings, characters designate several views,

Figure 1 is a plan view iron -with the handle and indicating in full lines the movable .switch practical embodi` had to the accomin which like reference the same parts in the andin whichof cap removed, and

an electric sad position of the to close the circuit, and in' dotted lines the changed position when the circuit is broken;

Fig. -2 is a'vertical longitudinal section of the main parts of the thermostat on the line 2-2 of Fig. 1;

Fig. 3 is a vertical transverse section on the line Fig. 4 is a 3-3 of Fig. 1;

diagram of the resistancecoils and wiring in connection with a side elevation of the contact springs and bridge piece operated by the thermostat gan Fig. 5v 1s atransverse sectional detail on the line 5-5 of Fig. 1.

Aother forms or types of heaters,

From what has been stated above, it will be understood that while I show a sad iron as an example of the Vutility of this device, the circuit breaker is adapted for use in such, for example, as bread toasters, car heaters, warming pads, etc. The illustration given, however, is Well adapted to indicate how the vinvention is particularly adapted for use in comparatively small or compendious inclosures.

Referring now more particularly to the drawings, I show at 10 a sad iron or base upon which the improved devices are secured. On or within this base is arranged any suitable. number or type of resistance coils 11the circuit through which includes a pair of spaced contact springs 12 adapted to be connected or bridged by a switch point 13 secured by an arm of insulation 14 to a link 15, the connection being made through a pair of clamps 16 or their equivalent, sccured to the free end of the insulation.

' The principal improvement lies in the thermostatic means for controlling the action or position of the contact piece 13. The primary element of the thermostat comprises a channel member 17 anchored rigidly at one end at 18 to the base 10. This point of connection 18 is adjacent one end of the base, and thence the channel member 17 extends towardqthe opposite end of the base, or, in other words, the thermostatic member 17 is practically as long as the dimensions of the supporting structure will warrant or permit. The orWa-rd end of the channel member 17 is provided with a laterally projecting lug 19 through which a pivot 2O connects the same to a lever 21 having longer and shorter arms, the longer arm being rigidly connected at the point 22to the link 15 above described.,

The second main portion of the thermostat comprises another expansion member 23 also shownin theJ form of a channel member and housed within the channel of the first expansion member 17, making a compact construction and one in which the parts mutually contribute to keep one another' in place. The front end of the second expansion member 23 is provided with an upwardly projecting lug 24 in which an adjustment screw 25 is swiveled, the screw being tapped through a bracket 26 fixed or anchored to lthe front end of the base at 27. For practical purposes this bracket and screw constitute an anchorage for the second expansion member. The -rear or opposite end, however, of this member is free to move independently of and within the first expansion member 17.

The third member ofthe thermostat isv indicated at 28, the same being a draft member ofl substantially the same length as the secondexpansion member and lying along the channel thereof. The rear ends of the second expansion member 23 and the draft member 28 are secured rigidly together at 29. The front end, however, of the draft member is adapted for movement independently pansion member.

of the adjacent. end of the expansion member in which it is mounted. Said front end of the draft member is provided with a laterally projecting lug 30 extending over and laterally beyond the llug A pivot 31 connects this outer'endof the lug 30 with the shorter arm cient of expansion. these parts is such that though the spacein which to operateis lextremely limited, I am having its front end 24 member will able to securea degree of expansion of the expansion members corresponding practically to a member of either of them. In other words, by connecting the parts as indicated, I rovide for the expansions of the members 1 and 23 to be 'added together through their respective r40' ratios of longer and shorter arms 'to actuate the switch pointv 13. V

.As will be noted from Fig. 1, the relative positions' of the pivots 20 and 31 with rel spect to the longitudinal axis of the thermostat determines the extent of oscillation of the point 22 `at the endr of the longer,` arm of the lever 21, and accordingly the position of .the contact piece 13. More definitely stated, considering the anchorage point 18 of the primary expansion member. as a starting point, the increase of heat. in the device will cause the elongation of the member 17 with a corresponding movement of the pivot 20 toward the front end of the base or to the left in Fig. 1. This movement of the pivot 20 would tend to throw the point of connection 22 likewise toward the left. Likewise, considering the second expansion member 23 as fixed with respect to same heat acting upon this cause the elongation thereof carrying the connecting point 29. toward the rear or toward the right in Fig.A 1. Since, however, the draft member 28'has comparathe base, the

tively little expansibility when subjected to the same heat as the other members, the elontive, and the 19 of the first extwice the length of 'point of `gation or expansion of the intermediate member 23 will carry the point 31 toward the right in Fig. l an amount approximately equal to the ,expansion of the member 23. It follows,'therefore, that with the point 20 moved to the left and the pivot point 31 moved to the right, the amount of elongation of the expansion members will be accumulasame, augmented by the disparity in lengths of the two,I arms of the lever 21, will cause sulicient lineal movement of the contact piece to throwv it into or out of contact with the springs 2() during the reasonable variations in heat subjected to the thermostat.

The thread of the screw 25 being regarded as right handed, a rotation or adjustment of the screw in a right handed directionY will cause" the expansion member 23, and that member connected thereto to be forced rearwith the result that the tendency of tact piece 13 from the springs. In other words, to adjust the device to break the circuit at a lowerY degree of heat, the screw is turned to the right, and. if greater heat is required the adjustment screw will be turned to the left. The device is simple in construction, neat and compact in installation, of dehy cate adjustment, and yet safe and reliable in practical operation.

I claim l A,

1. In a thermostatic circuit closer, thel combination of relatively fixed and movable contact members, a lever having longer and shorter arms, the longer arm being connected to the movable contact member, a pair of expansion members arranged parallel to each other, one of said members being anchored at oneend and the other member being anchored at its opposite end, and means to connect the otherwise free ends of lthe expansion members to said lever whereby the effect of the expansion of one member acting upon the lever will be added to that of the other expansion member.

2. In a thermostatic 'circuit closer, the combination with relatively fixed and movable contact members, of a thermostat connected to the movable member and comprising a lever, ranged and guided one within the other and of approximately the same length, means to fix one end of one member in stationary position, means to anchor theopposite end of -the other member in position, the otherwise free end of one of the expansion members being pivoted to the lever, and a draft member extending from the otherwise free end of the other expansion member to a pivotal connection with said lever, the two the lever and the two expansion members being movable relatively in opposite direcpivotal connecting points between" a pair of expansion members arf.

tions whereby the expansion of the two mem- 13g bers is accumulative as made elective upon the movable contact member through said lever. u

3. In a device of the character set forth, the combination of a pair of expansion members one arranged Within the other, means to anchor opposite ends of these two members respectively in fixed position, a lever extending laterally with respect to the longitudinal axis of said expansion members, and means to connect the otherwise free ends of the expansion members respectively to independent points of said lever whereby theexpansion of said expansion members tends to vary they angle between the lever and said axis. l p

4. In a device of the character set forth,

bers.

MICHAEL HOUGH FARLEY. Witnesses:

NELSON HUGHES, H. J. WAmiER.

of the irst mentioned v 

